<!DOCTYPE html>
<html>

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meat name="viewpoet" content="with=device-width, initial-scale=1.0">
        <title>Document</title>
</head>

<body>
    <div id="app">
        <!-- v-on: 可以简写成 @ -->
        <button @click="count--">-</button>
        <!-- <button v-on:mouseenter="count--">-</button> 鼠标放上去就是一个事件-->
        <span>{{count}}</span>
        <button v-on:click="count++">+</button>
        <!-- <button v-on:click="count=count+2">+</button>   鼠标点击事件 -->
    </div>
    <!-- 引入的是开发版本包 - 包含完整的注释和警告 -->
    <script src="https://cdn.jsdelivr.net/npm/vue@2.7.16/dist/vue.js"></script>
    <script>
        const app = new Vue({
            el: '#app',
            data: {
                count: 100
            }
        }) 
    </script>

</body>

</html>